Aerobic oxidation of 2,4,6-tri-tert-butylphenol to quinones catalyzed by copper(II) complexes of an N-octylated bis-benzimidazolyl ligand
作者： Anjana Yadav , Pavan Mathur
DOI: 10.1016/J.ICA.2015.06.026
关键词:
摘要: Abstract Copper(II) complexes of a N-octylated bisbenzimidazolyl ligand are synthesized and characterized. These carry out the oxidative dealkylation 2,4,6-tri-tertbutylphenol (TTBP) using molecular oxygen to 2,6-ditertbutylbenzoquinone 4,6-di-tertbutylbenzoquinone. The oxidation proceeds via phenoxyl radical species detected spectrophotometrically, by EPR. A reactive copper(II)-dioxygen is involved that carries reaction. comparison rates formation 4,6-di-tert-butylbenzoquinone versus 2,6-di-tert-butylbenzoquinone suggests alternative pathway may exist for para-quinone derivative. Isolation an intermediate 4,4′-peroxybis(2,4,6-tri-tert-butylcyclohexa-2,5-dienone its structural characterization supports above contention.
sci-hub.se 参考文章(29)
Gennadiĭ Efremovich Zaikov, Z. K. Maĭzus, N. M. Ėmanuėlʹ, Oxidation of organic compounds : medium effects in radical reactions Pergamon Press. ,(1984)
Subrata Mandal, Dainius Macikenas, John D. Protasiewicz, Lawrence M. Sayre, Novel tert-butyl migration in copper-mediated phenol ortho-oxygenation implicates a mechanism involving conversion of a 6-hydroperoxy-2,4-cyclohexadienone directly to an o-quinone Journal of Organic Chemistry. ,vol. 65, pp. 4804- 4809 ,(2000) , 10.1021/JO991625M
W.J. Geary, The use of conductivity measurements in organic solvents for the characterisation of coordination compounds Coordination Chemistry Reviews. ,vol. 7, pp. 81- 122 ,(1971) , 10.1016/S0010-8545(00)80009-0
Alan Zombeck, Russell S. Drago, Barry B. Corden, John H. Gaul, Activation of Molecular Oxygen: Kinetic Studies of the Oxidation of Hindered Phenols with Cobalt-Dioxygen Complexes. Journal of the American Chemical Society. ,vol. 103, pp. 7580- 7585 ,(1981) , 10.1021/JA00415A027
Virginia W. Manner, Todd F. Markle, John H. Freudenthal, Justine P. Roth, James M. Mayer, The first crystal structure of a monomeric phenoxyl radical: 2,4,6-tri-tert-butylphenoxyl radical Chem. Commun.. pp. 256- 258 ,(2008) , 10.1039/B712872J
Ruchi Bakshi, Pavan Mathur, Organo-peroxyl compounds via catalytic oxidation of a hindered phenol and aniline utilizing new manganese(II) bis benzimidazole diamide based complexes Inorganica Chimica Acta. ,vol. 363, pp. 3477- 3488 ,(2010) , 10.1016/J.ICA.2010.06.064
Akira Nishinaga, Haruo Tomita, Kanji Nishizawa, Teruo Matsuura, Shunichiro Ooi, Ken Hirotsu, Regioselective formation of peroxyquinolatocobalt(III) complexes in the oxygenation of 2,6-di-t-butylphenols with cobalt(II) Schiff-base complexes Journal of the Chemical Society, Dalton Transactions. pp. 1504- 1514 ,(1981) , 10.1039/DT9810001504
A. Latif Abuhijleh, Mononuclear copper(ll) aspirinate or salicylate complexes with methylimidazoles as biomimetic catalysts for oxidative dealkylation of a hindered phenol, oxidation of catechol and their superoxide scavenging activities Inorganic Chemistry Communications. ,vol. 14, pp. 759- 762 ,(2011) , 10.1016/J.INOCHE.2011.02.029
Grzegorz Litwinienko, A. L. J. Beckwith, K. U. Ingold, The frequently overlooked importance of solvent in free radical syntheses Chemical Society Reviews. ,vol. 40, pp. 2157- 2163 ,(2011) , 10.1039/C1CS15007C
Kuldeep Mahiya, Ravinder Kumar, Francisco Lloret, Pavan Mathur, Oxidation of substituted phenols using copper(II) metallatriangles formed through ligand sharing Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy. ,vol. 133, pp. 663- 668 ,(2014) , 10.1016/J.SAA.2014.06.026